With the fall of the Iron Curtain and the breakup of the Soviet Union, it has become necessary to remove toxic (chemical material) munitions stored by NATO and the U.S. Government in Germany and elsewhere. These munitions include 155 mm projectiles and an 8-inch projectile designated M426 adapted for delivering chemical weapons. Routine inspections of munitions storage sites have revealed that a small number of stored 155 mm projectiles leak. Propellant charge containers were considered adequate for limited storage at such facilities, but it soon became apparent that such containers would not be adequate to store toxic munitions for longer periods of time and would not withstand the handling necessary to move such munitions.
Single round containers (SRC) were developed to house for transport 155 mm projectiles, 8-inch projectiles, bent projectiles, and projectiles with diameters of 12 inches. Each SRC was designed to enclose a single toxic agent munition and to prevent leakage of any agent material. The body of an SRC was fabricated by welding a flange and a domed elliptical head to a tubular body. A similar flanged head assembly was then attached to the body flange. Between the flanges was provided a butyl rubber O-ring as a barrier for leaking toxic chemical agents. Screw fasteners about the flange body were used for sealing the container.
It was later determined that the agent fill of such munitions included a chemical or chemicals that deteriorate carbon products, and over time and exposure to such chemicals the butyl rubber could break down, thus compromising the integrity of the container seal.